Ref. Ares(2018)5582208 - 31/10/2018 Fishfriendly Innovative Technologies for Hydropower Funded by the Horizon 2020 Framework Programme of the European Union D1.2 Risk classification of European lampreys and fish species Project Acronym FIThydro Project ID 727830 Work package 1 Deliverable Coordinator Christian Wolter Author(s) Christian Wolter (IGB), Ruben van Treeck (IGB), Johannes Radinger (IGB), Nicole Smialek (TUM), Joachim Pander (TUM), Melanie Müller (TUM), Jürgen Geist (TUM) Deliverable Lead beneficiary TUM, FVB.IGB Dissemination Level Public Delivery Date 31 October 2018 Actual Delivery Date 31 October 2018 Acknowledgement This project has received funding from the European Union’s Horizon 2020 research and inno- vation program under grant agreement No 727830. Executive Summary Aim After having analysed the species-specific sensitivity against mortality, i.e. the species’ intrinsic resilience, this study aimed to characterise the potential impacts of hydropower on fish. The main objective was to analyse the principal operation related impacts of hydropower and identify species most at risk. The results provide the operation related component or baseline for devel- oping a fish population hazard index for the European fish fauna. Methods Three principal operation related impacts of hydropower have been identified: i) migration bar- rier, ii) mortality, and iii) habitat loss due to impoundments. Migration barriers notably affect diadromous fish, which are obligatory migrants, moving between freshwater and marine envi- ronments. Mortality has been quantified and classified primarily during turbine passage. Other types of hydropower induced mortality, e.g. at trash racks, could not be quantified. Habitat loss due to impoundments has been attributed to hydromorphological processes and related habitat characteristics. Correspondingly, lithophilic, i.e. gravel spawning species were identified experi- encing the highest impacts of habitat loss due to impounding rivers. Species were classified at very high risk from hydropower operations, if at least three of the four following conditions were fulfilled: i) belonging to the high or highest sensitivity class, ii) having high or highest mortality risk during turbine passage, iii) being diadromous, and iv) being lithophilic. Species were classified as high risk in hydropower environments, if two of the conditions men- tioned above were fulfilled, and they were classified as lower risk, if only one or none of the conditions were fulfilled. Results The sensitivity matrix contains 148 native European fish and lamprey species occurring in Eu- ropean waters. Of these, 18 species were classified as having the highest sensitivity and 29 with high sensitivity. Twenty two of the classified species are diadromous. The habitat degradation and loss in the impoundment particularly affect lithophilic fish, which represent a total of 76 species. The mortality was empirically derived from turbine passage studies. Data were gathered for 42 species in total, of which 20 had a sufficient sample size. The data could be used to derive a model to assess the length dependent potential mortality risk for data deficient species. However, here only the empirical data for the 36 species occurring in more than one study with more than one specimen provided in Table 4 were used for identifying species’ mortality risk. Combining the intrinsic sensitivity of species and the operation related impacts of hydropower, as mentioned above, 21 and 25 species face a very high and high risk, respectively. Among the species at very high risk, there are several candidate species to be considered for environmental impact assessment, as well as mitigation for various river types, e.g., the diadromous salmonids or the large bodied cyprinids, like barbel, nase, asp, and ide, but also the smaller bodied dace. Specific spatial and habitat requirements have been compiled for a range of riverine species, although data availability was very heterogeneous and for most species very limited and data quality highly incoherent among different studies. 727830 FIThydro - Deliverable 1.2 - Page 2 of 39 Table of Contents Executive Summary ............................................................................................................... 2 List of Figures ......................................................................................................................... 3 List of Tables .......................................................................................................................... 4 1. Background ..................................................................................................................... 5 2. Methods .......................................................................................................................... 6 2.1 Sensitivity matrix ...................................................................................................... 6 2.2 Fish mortality at hydropower plants .......................................................................... 6 2.3 Habitat alteration in impoundments .......................................................................... 8 3. Results ............................................................................................................................ 9 3.1 Sensitivity matrix ...................................................................................................... 9 3.2 Fish mortality at turbines ........................................................................................ 13 3.3 Habitat requirements .............................................................................................. 22 3.4 Synthesis ............................................................................................................... 33 4. Conclusions ................................................................................................................... 36 5. References .................................................................................................................... 37 List of Figures Figure 1: Observed species-specific turbine mortality rates at hydropower plants. ............... 14 Figure 2: Robust empirical species-specific turbine mortality rates at hydropower plants ..... 15 Figure 3: Observed species-specific turbine mortality rates at hydropower plants ................ 16 Figure 4: Observed range of substrate particle sizes in spawning grounds and juvenile habitats ................................................................................................................................ 25 Figure 5: Observed depths of eggs in the interstitial space. .................................................. 26 Figure 6: Observed incubation times in degree days for egg development of gravel-spawning fish species. ......................................................................................................................... 27 Figure 7: Observed range of preferred surface flow velocities at spawning grounds and juvenile habitats.................................................................................................................... 28 Figure 8: Observed range of preferred water depths at spawning grounds and juvenile habitats ................................................................................................................................ 29 Figure 9 Reported ranges of individual spawning sites. ........................................................ 30 Figure 10: Reported ranges of spawner densities at gravel spawning grounds. ................... 31 Figure 11: Reported juvenile densities in nursing grounds. ................................................... 33 727830 FIThydro - Deliverable 1.2 - Page 3 of 39 List of Tables Table 1: Sensitivity classification of 148 native European fish and lamprey species. ............ 10 Table 2: Calculated length of fish facing a mortality risk during turbine passage................... 17 Table 3: Species-specific potential mortality risk at hydropower plants during turbine passage. ............................................................................................................................................. 18 Table 4: Species intrinsic sensitivity versus empirical species-specific mortality at hydropower turbine passage. ................................................................................................................... 21 Table 5: Overview of reproduction traits and abiotic environmental conditions in spawning and nursing habitats. ............................................................................................................ 22 Table 6: Metadata of available information on environmental conditions in spawning and nursing habitats .................................................................................................................... 23 Table 7: Overview of reported traits for Salmo trutta. ............................................................ 32 Table 8: Summary of native European lamprey and fish species of high and very high risk during hydropower operation. ............................................................................................... 35 727830 FIThydro - Deliverable 1.2 - Page 4 of 39 1. Background Assessing the impact of hydropower plants on different fish species and communities is a key component of supporting decisions during the commission and operation of hydropower facili- ties. Therefore, work package